# Cookbook/Lists and strings

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## 1 Strings

Since strings are lists of characters, you can use any available list function.

### 1.1 Combining strings

Problem Solution Examples
combining two strings (++)
`"foo" ++ "bar"                  --> "foobar"`
combining many strings concat
`concat ["foo", "bar", "baz"]    --> "foobarbaz"`

### 1.2 Accessing substrings

Problem Solution Examples
`head "foo bar baz"      --> 'f'`
accessing the last character last
`last "foo bar baz"      --> 'z'`
accessing the character at a given index (!!)
`"foo bar baz" !! 4      --> 'b'`
accessing the first `n` characters take
`take 3 "foo bar baz"    --> "foo"`
accessing the last `n` characters TODO TODO
accessing the `n` characters starting from index `m` drop, take
`take 4 \$ drop 2 "foo bar baz"    --> "o ba"`

### 1.3 Splitting strings

Problem Solution Examples
splitting a string into a list of words words
`words "foo bar\t baz\n"        --> ["foo","bar","baz"]`
splitting a string into two parts splitAt
`splitAt 3 "foo bar baz"    --> ("foo"," bar baz")`

### 1.4 Multiline strings

```"foo\
\bar"               --> "foobar"```

### 1.5 Converting between characters and values

Problem Solution Examples
converting a character to a numeric value ord
```import Char
ord 'A'    --> 65```
converting a numeric value to a character chr
```import Char
chr 99     --> 'c'```

### 1.6 Reversing a string by words or characters

Problem Solution Examples
reversing a string by characters reverse
`reverse "foo bar baz"                        --> "zab rab oof"`
reversing a string by words words, reverse, unwords
`unwords \$ reverse \$ words "foo bar baz"      --> "baz bar foo"`
reversing a string by characters by words words, reverse, map, unwords
`unwords \$ map reverse \$ words "foo bar baz"  --> "oof rab zab"`

### 1.7 Converting case

Problem Solution Examples
converting a character to upper-case toUpper
```import Char
toUpper 'a'            --> "A"```
converting a string to upper-case toUpper, map
```import Char
map toUpper "Foo Bar"  --> "FOO BAR"```
converting a character to lower-case toLower
```import Char
toLower 'A'            --> "a"```
converting a string to lower-case toLower, map
```import Char
map toLower "Foo Bar"  --> "foo bar"```

TODO

### 1.9 Performance

For high performance requirements (where you would typically consider C), consider using Data.ByteString.

TODO